Ray Kurzwel. The ultimate thinking machine.

In 1965 host Steve Allen introduced a quiet, diffident 16-year-old on the TV game show I've Got a Secret. A music selection was played, and the celebrity contestants began their questioning. In the end, film star Henry Morgan, not former Miss America Bess Myerson, finally guessed the secret: The boy had designed a computer that could listen to music and then compose its own original notes based on what it had heard.

No one knew it then, but inventor/entrepreneur Ray Kurzweil had taken his first step toward a goal that would occupy much of his working life: developing a computer that could recognize human speech.

Commercial speech recognition products have been around since the mid-'70s, but the early ones were expensive, had limited vocabularies, and required speakers to talk...very...very...slowly. But in recent years, with certain enabling technologies in place and the advent of powerful and cheap PCs, products have come way down in price -- and demand has blossomed.

Investors at Charles Schwab are using speech recognition to access stock prices. United Airlines's 80,000 employees are using voice commands to make travel arrangements. And now, when the boss says to take a letter, the secretary could well be a computing machine.

Back in 1982 Kurzweil, with his former college roommate, Aaron Kleiner, started Kurzweil Applied Intelligence (KAI) to find what those in the industry call the "holy grail" -- computers capable of handling an individual's unique, continuous speech. Their brand-new company stepped into an environment that, as Kleiner remembers it, was "hostile."

Early government-funded speech recognition projects had failed, and the general public expected nothing less than the all-knowing voice of HAL. Future prospects looked dim.

What was needed was nothing less than brute force, extremely fast computers capable of handling the algorithms necessary to understand the vagaries of human speech -- our accents, languages, squeaks, and squawks. Not needed were the 90-pound weaklings of the mid-'80s: The Apple IIes with a clock speed of 1 and a "whopping" 128K memory.

Kurzweil clearly had his work cut out for him. But he did have a few weapons on his side. First, he had an almost religious belief in Moore's Law. Wait long enough, he knew, and extremely fast PCs would be available. He was also a genius. At MIT, where he earned a computer science and creative writing degree, he managed to pull down A's even though he was known as "the phantom" because he rarely went to class. Also to his advantage was his longtime fascination with pattern recognition, which forms the basis for human speech recognition. (That "composing computer" he built in high school was based on pattern recognition).

Kurzweil also had survived the perils of entrepreneurism. He had groveled for VC funding and had been forced to pawn extra equipment to pay the bills. His first company, which he started in the mid-'70s, had been a success. Kurzweil Computer Products created a reading machine for the blind, which was hailed as the most significant step forward since Braille, and was later sold to Xerox for $6 million.

All of this added to KAI's early success. In 1985 the company identified an early adopting market for its limited-vocabulary dictation system: radiologists. Two years later it introduced an even faster system.

Ironically, though, over the long term KAI struggled and fell behind its two toughest rivals, IBM and Dragon Systems, each of which released holy grail products before KAI. In 1997 KAI was sold to Belgium-based Lernout & Hauspie.

John Oberteuffer, president of Voice Information Associates, a speech recognition consulting company, explains one possible reason for the company's problems: "Ray's an early-stage entrepreneur" whose strengths are not necessarily managing a mature company.

While Kurzweil did not see his company reach the finish line first, his greatest impact came -- as inventors' often do -- early in the technology's development. He spent hours promoting the industry at trade shows. Says Judith Markowitz, author of Using Speech Recognition, "It didn't matter if the product failed or succeeded because it moved the industry forward." Says futurist George Gilder, "Ray pioneered and popularized speech recognition."

Kurzweil's long-term impact, however, is much greater than just speech recognition. His belief in the exponential growth of technology gives voice to humanity's possibilities. He is a visionary whose predictions are based on hard science. There is no way the march of technology will stop, he says. It will continue to increase exponentially until it "ultimately creates itself."